Editing Axolotl (section)

==Relation to humans==
=== Research history ===
Six adult axolotls (including a leucistic specimen) were shipped from [[Mexico City]] to the ''[[Jardin des Plantes]]'' in Paris in 1863. Unaware of their neoteny, [[Auguste Duméril]] was surprised when, instead of the axolotl, he found in the vivarium a new species, similar to the salamander.{{verify source|reason=French language verification needed|date=November 2021}} This discovery was the starting point of research about neoteny. It is not certain that ''[[Ambystoma velasci]]'' specimens were not included in the original shipment.{{Citation needed|date=October 2021}} Vilem Laufberger in Prague used thyroid hormone injections to induce an axolotl to grow into a terrestrial adult salamander. The experiment was repeated by Englishman [[Julian Huxley]], who was unaware the experiment had already been done, using ground thyroids.<ref name=":4">{{Cite journal|last1=Reiß|first1=Christian|last2=Olsson|first2=Lennart|last3=Hoßfeld|first3=Uwe|date=2015|title=The history of the oldest self-sustaining laboratory animal: 150 years of axolotl research|url=https://onlinelibrary.wiley.com/doi/abs/10.1002/jez.b.22617|journal=Journal of Experimental Zoology Part B: Molecular and Developmental Evolution|language=en|volume=324|issue=5|pages=393–404|doi=10.1002/jez.b.22617|pmid=25920413|bibcode=2015JEZB..324..393R |issn=1552-5015}}</ref> Since then, experiments have been done often with injections of iodine or various thyroid hormones used to induce metamorphosis.<ref name=":5">{{Cite journal|last1=Safi|first1=Rachid|last2=Bertrand|first2=Stéphanie|last3=Marchand|first3=Oriane|last4=Duffraisse|first4=Marilyne|last5=de Luze|first5=Amaury|last6=Vanacker|first6=Jean-Marc|last7=Maraninchi|first7=Marie|last8=Margotat|first8=Alain|last9=Demeneix|first9=Barbara|last10=Laudet|first10=Vincent|date=2004-02-01|title=The Axolotl (''Ambystoma mexicanum''), a Neotenic Amphibian, Expresses Functional Thyroid Hormone Receptors|journal=Endocrinology|volume=145|issue=2|pages=760–772|doi=10.1210/en.2003-0913|pmid=14576183 |doi-access=free}}</ref>

===Use as a model organism===
[[File:Desarrollo de huevo de axolote Ambystoma Mexicanum.jpg|thumb|Stages of development]]
Today, the axolotl is still used in research as a [[model organism]], and large numbers are bred in captivity. They are especially easy to breed compared to other salamanders in their family, which are rarely captive-bred due to the demands of terrestrial life. One attractive feature for research is the large and easily manipulated [[embryo]], which allows viewing of the full development of a vertebrate. Axolotls are used in [[heart defects|heart defect]] studies due to the presence of a mutant gene that causes heart failure in embryos. Since the embryos survive almost to hatching with no heart function, the defect is very observable. Further research has been conducted to examine their heart as a model of a single human [[Ventricle (heart)|ventricle]] and excessive trabeculation.<ref>{{Cite journal |last1=Meyer |first1=Sophie |last2=Lauridsen |first2=Henrik |last3=Pedersen |first3=Kathrine |last4=Andersson |first4=Sofie Amalie |last5=van Ooij |first5=Pim |last6=Willems |first6=Tineke |last7=Berger |first7=Rolf M. F. |last8=Ebels |first8=Tjark |last9=Jensen |first9=Bjarke |date=2022-11-28 |title=Opportunities and short-comings of the axolotl salamander heart as a model system of human single ventricle and excessive trabeculation |journal=Scientific Reports |language=en |volume=12 |issue=1 |pages=20491 |doi=10.1038/s41598-022-24442-9 |issn=2045-2322 |pmc=9705478 |pmid=36443330|bibcode=2022NatSR..1220491M }}</ref> The axolotl is also considered an ideal animal model for the study of [[neural tube]] closure due to the similarities between human and axolotl [[neural plate]] and tube formation; the axolotl's neural tube, unlike the frog's, is not hidden under a layer of superficial [[epithelium]].<ref>{{Cite journal |last=Gordon |first=R. |date=1985 |title=A review of the theories of vertebrate neurulation and their relationship to the mechanics of neural tube birth defects |url= https://journals.biologists.com/dev/content/89/Supplement/229 |journal= [[Journal of Embryology and Experimental Morphology]] |volume=89 |issue=Supplement |pages= 229–255 |pmid=3913733}}</ref> There are also mutations affecting other organ systems some of which are not well characterized and others that are.<ref>{{Cite journal |last=Armstrong |first=John B. |date=1985 |title= The axolotl mutants |journal= [[Developmental Genetics]] |volume=6 |issue=1 |pages=1–25 |doi=10.1002/dvg.1020060102}}</ref> The genetics of the color variants of the axolotl have also been widely studied.<ref name= "Color Atlas of Pigment Genes"/>

===Captive care===
{{See also|Herpetoculture}}
[[File: Axolotl with Grit XRay.png|thumb|upright=0.6|This animal was X-rayed several times as part of a research project over a period of two years. It was a normal healthy adult (26.3 cm; 159.5 gm) at the beginning of the project and lived several more years after the project ended.<ref name=kulbisky>{{Cite journal |last1=Kulbisky |first1=Gordon P |last2=Rickey |first2=Daniel W |last3=Reed |first3=Martin H |last4=Björklund |first4=Natalie |last5=Gordon |first5=Richard |date=1999 |title=The axolotl as an animal model for the comparison of 3-D ultrasound with plain film radiography |journal=Ultrasound in Medicine and Biology |volume=25 |issue=6 |pages=969–975 |doi=10.1016/s0301-5629(99)00040-x|pmid=10461726 }}</ref>]]

The axolotl is a popular exotic pet like its relative, the tiger salamander (''Ambystoma tigrinum''). As for all [[poikilotherm]]ic organisms, lower temperatures result in slower metabolism and a very unhealthily reduced appetite. Temperatures at approximately {{convert|16|C|F}} to {{convert|18|C|F}} are suggested for captive axolotls to ensure sufficient food intake; stress resulting from more than a day's exposure to lower temperatures may quickly lead to disease and death, and temperatures higher than {{convert|24|C|F}} may lead to metabolic rate increase, also causing stress and eventually death.<ref>{{Cite web|url=http://www.axolotl.org/requirements.htm|title=Axolotls – Requirements & Water Conditions in Captivity|website=axolotl.org|access-date=2016-03-14}}</ref><ref>{{Cite web|url=http://www.caudata.org/cc/species/Ambystoma/A_mexicanum.shtml|title=Caudata Culture Species Entry – ''Ambystoma mexicanum'' – Axolotl|website=www.caudata.org|access-date=2016-03-14|archive-date=2016-03-15|archive-url=https://web.archive.org/web/20160315031956/http://www.caudata.org/cc/species/Ambystoma/A_mexicanum.shtml|url-status=dead}}</ref> [[Chlorine]], commonly added to [[tapwater]], is harmful to axolotls. A single axolotl typically requires a {{convert|150|L|gal|adj=on|abbr=off}} tank. Axolotls spend the majority of the time at the bottom of the tank.<ref>{{Cite web |url=https://www.tfhmagazine.com/articles/freshwater/axolotls-keeping-a-water-monster-full |last=Wiegert |first=Joshua |title=Axolotls: Keeping a Water Monster}}</ref>

Salts, such as [[Holtfreter's solution]], are often added to the water to prevent infection.<ref>{{cite web|last=Clare|first= John P. |url=http://www.axolotl.org/health.htm |title=Health and Diseases|website=axolotl.org}}</ref> Among hobbyists, the process of artificially inducing metamorphosis can often result in death during or even following a successful attempt, and so casual hobbyists are generally discouraged from attempting to induce metamorphosis in pet axolotls.<ref name=":6" /> Morphed pet axolotls should be given solid footholds in their enclosure to satisfy their need for land. They should not be given live animals as food.<ref>{{cite web |title=Transition & Feeding |url=https://www.morphedaxolotls.com/transition-and-feeding |website=Morphed Axolotls |language=en}}</ref>

In captivity, axolotls eat a variety of readily available foods, including trout and salmon pellets, frozen or live [[Glycera (genus)|bloodworm]]s, [[earthworm]]s, and [[waxworm]]s. Axolotls can also eat [[feeder fish]], but care should be taken as fish may contain parasites.<ref>{{Cite journal | doi=10.1577/03632415.2011.10389070|title = The Aquarium Trade as an Invasion Pathway in the Pacific Northwest| journal=Fisheries| volume=36| issue=2| pages=74–85|year = 2011|last1 = Strecker|first1 = Angela L.| last2=Campbell| first2=Philip M.| last3=Olden| first3=Julian D.| bibcode=2011Fish...36...74S |url = https://pdxscholar.library.pdx.edu/esm_fac/40}}</ref>

Substrates are another important consideration for captive axolotls, as axolotls (like other amphibians and reptiles) tend to ingest bedding material together with food<ref name=Pough /> and are commonly prone to gastrointestinal obstruction and foreign body ingestion.<ref>{{cite journal|title=Amphibian Emergency Medicine|journal=Veterinary Clinics of North America: Exotic Animal Practice|volume=10|issue=2|pages=587–620|doi=10.1016/j.cvex.2007.02.004|pmid=17577564|year=2007|last1=Clayton|first1=Leigh Ann|last2=Gore|first2=Stacey R.}}</ref> Some common substrates used for animal enclosures can be harmful for amphibians and reptiles. Gravel (common in aquarium use) should not be used, and is recommended that any sand consists of smooth particles with a grain size of under 1mm.<ref name=Pough>{{cite web|last=Pough|first=F. H.|url=http://netvet.wustl.edu/species/reptiles/pough.txt|title=Recommendations for the Care of Amphibians and Reptiles in Academic Institutions|publisher=National Academy Press|location=Washington, D.C.|year=1992}}</ref> One guide to axolotl care for laboratories notes that bowel obstructions are a common cause of death, and recommends that no items with a diameter below 3&nbsp;cm (or approximately the size of the animal's head) should be available to the animal.<ref name=Gresens>{{cite journal|last1=Gresens|first1=Jill|title=An Introduction to the Mexican Axolotl (''Ambystoma mexicanum'')|journal=Lab Animal|volume=33|issue=9|year=2004|pages=41–47|doi=10.1038/laban1004-41|pmid=15457201|s2cid=33299160}}</ref>

There is some evidence that axolotls might seek out appropriately-sized gravel for use as [[gastroliths]]<ref>Wings, O [http://www.dinosaurhunter.org/files/app-2007-wings-gastrolith_function_classification.pdf A review of gastrolith function with implications for fossil vertebrates and a revised classification] {{Webarchive|url=https://web.archive.org/web/20160304062304/http://www.dinosaurhunter.org/files/app-2007-wings-gastrolith_function_classification.pdf |date=2016-03-04 }} Acta Palaeontologica Polonica 52 (1): 1–16</ref> based on experiments conducted at the University of Manitoba axolotl colony.<ref>Gordon, N, [https://embryogenesisexplained.org/2015/09/10/gastroliths-how-i-learned-to-stop-worrying-and-love-gravel/ Gastroliths – How I Learned to Stop Worrying and Love Gravel.] {{Webarchive|url=https://web.archive.org/web/20200922142827/https://embryogenesisexplained.org/2015/09/10/gastroliths-how-i-learned-to-stop-worrying-and-love-gravel/ |date=2020-09-22 }}</ref><ref>Björklund, N.K. (1993). Small is beautiful: economical axolotl colony maintenance with natural spawnings as if axolotls mattered. In:  Handbook on Practical Methods. Ed.: G.M. Malacinski & S.T. Duhon. Bloomington, Department of Biology, Indiana University: 38–47.</ref> As there is no conclusive evidence pointing to gastrolith use, gravel should be avoided due to the high risk of [[Impaction (animals)|impaction]].<ref>{{Cite journal|last=Loh|first=Richmond|date=2015-05-15|title=Common Disease Conditions in Axolotls|website=Vin.com |url=https://www.vin.com/apputil/content/defaultadv1.aspx?pId=14365&catId=73681&id=7259254|url-status=live|access-date=2022-01-21|archive-url=https://web.archive.org/web/20200804110231/https://www.vin.com/apputil/content/defaultadv1.aspx?pId=14365&catId=73681&id=7259254 |archive-date=2020-08-04 }}</ref>

<gallery widths=200 heights=160>
File: Ambystoma mexicanum at Vancouver Aquarium.jpg|These axolotls at [[Vancouver Aquarium]] are [[leucistic]], with less pigmentation than normal.
File:Axolotl in a Pet store in Melbourne.jpg|Axolotl in a pet store in Melbourne, Australia
File:Axolotls in Kew Gardens.jpg|Axolotls in a [[pond]] with ''[[Pistia]]'', [[Kew Gardens]]
</gallery>

=== Cultural significance ===
[[File:Edoardo Aldama.jpg|thumb|As [[graffiti]], Mexico City]]
The species is named after the [[Aztec deity]] [[Xolotl]], the god of fire and lightning, who transformed himself into an axolotl to avoid being sacrificed by fellow gods. They continue to play an outsized cultural role in Mexico.<ref name="Reuters2018">{{Cite news |last=Garcia |first=David Alire |date=2018-11-20 |title=Mexico's axolotl, a cartoon hero and genetic marvel, fights for survival |url=https://www.reuters.com/article/us-mexico-axolotl-idUSKCN1NP0F6 |access-date=2022-08-16 |work=Reuters |language=en}}</ref> Axólotl also means water monster in the [[Nahuatl]] language.

They appear in the works of Mexican muralist [[Diego Rivera]]. In 2021, [[Mexico]] released a new design for its 50-[[Mexican peso|peso]] banknote featuring an axolotl along with [[maize]] and [[chinampa]]s on its back.<ref>{{Cite web |date=2020-02-21 |title=Mexican axolotl will be the new image of the 50 peso bill |url=https://www.theyucatantimes.com/2020/02/mexican-axolotl-will-be-the-new-image-of-the-50-peso-bill/ |access-date=2025-04-24 |website=The Yucatan Times |archive-url=https://web.archive.org/web/20250210125136/https://www.theyucatantimes.com/2020/02/mexican-axolotl-will-be-the-new-image-of-the-50-peso-bill/ |archive-date=10 February 2025 |language=en-US}}</ref><ref>{{Cite web |title=Billete de 50 pesos de la familia G |url=https://www.banxico.org.mx/billetes-y-monedas/billete-50-pesos-familia-g.html |access-date=2023-02-20 |website=www.banxico.org.mx |language=es}}</ref> It was recognized as "Bank Note of the Year" by the [[International Bank Note Society]].<ref>{{Cite web |title=Banknote of 2021 Nominations |url=https://www.theibns.org/joomla/index.php?option=com_content&view=article&id=809:banknote-of-2021-nominations&catid=39:banknote-of-2021&Itemid=51 |access-date=2023-02-20 |website=www.theibns.org}}</ref> [[HD 224693]], a [[star]] in the [[Celestial equator|equatorial]] [[constellation]] of [[Cetus]], was named Axólotl in 2019.<ref>{{Cite web |title=Approved names |url=http://www.nameexoworlds.iau.org/final-results |access-date=2020-01-02 |website=www.nameexoworlds.iau.org |language=en}}</ref><ref>{{Cite web |date=December 17, 2019 |title=100 000s of People from 112 Countries Select Names for Exoplanet Systems In Celebration of IAU's 100th Anniversary |url=https://www.iau.org/news/pressreleases/detail/iau1912/ |access-date=2020-01-02 |website=[[International Astronomical Union]]}}</ref>

In the [[21st century]], axolotls became renowned as a [[cultural icon]], the species' [[wikt:likeness|likeness]] appearing in or inspiring various aspects of contemporary media, such as [[television show]]s, [[movie]]s, or [[video game]]s. The [[List of Pokémon|Pokémon]] [[Mudkip]] and its evolutions, added in ''[[Pokémon Ruby and Sapphire]]'' (2002), take some visual inspiration from axolotls.<ref name="Reuters2018" /> Additionally, the Pokémon [[Wooper]], added in ''[[Pokémon Gold, Silver, and Crystal|Pokémon Gold, Silver and Crystal]]'' (1999), is directly based on an axolotl.<ref name="Reuters2018" />{{Additional citation needed|date=May 2023}} The dragon Toothless in the ''[[How to Train Your Dragon]]'' movies was modeled after axolotls as well.<ref name="Reuters2018" /> Following [[Mojang Studios]]' trend of adding endangered species to the game to raise awareness, axolotls were added to the video game ''[[Minecraft]]'' in 2020,<ref>{{Cite web |last=Minecraft |date=October 3, 2020 |title="Minecraft Live: Caves & Cliffs - First Look" |url=https://www.youtube.com/watch?v=DBvZ2Iqmm3M&t=2486s |website=[[YouTube]] |quote="And then we also found out that axolotls are endangered in the real world, and we think it's good to add endangered animals to Minecraft to create awareness about that." - Agnes Larsson}}</ref> and were included in its spin-offs ''[[Minecraft Dungeons|Minecraft: Dungeons]]'' and ''[[Lego Minecraft]]''.<ref>{{Cite web |title=The Guardian Battle 21180 |url=https://www.lego.com/en-us/product/the-guardian-battle-21180 |access-date=2023-02-20 |website=www.lego.com |language=en}}</ref><ref>{{Cite web |title=The Axolotl House 21247 |url=https://www.lego.com/en-us/product/the-axolotl-house-21247 |access-date=2024-12-27 |website=www.lego.com |language=en}}</ref> An anthropomorphic axolotl named Axo was added as a purchasable outfit in ''[[Fortnite Battle Royale]]'' on August 9, 2020.<ref>{{cite web |date=5 August 2020 |title=Fortnite v13.40 Leaked Skins: Axo, Castaway Jonesy, Crustina & More |url=https://culturedvultures.com/fortnite-v13-40-leaked-skins-axo-castaway-jonesy-crustina/}}</ref><ref>{{cite tweet|number=1425245581480448005|user=FortniteGame|title=Axo got a new style just in time for @maisie_williams & @reubenSelby's hand-picked Locker Bundle}}</ref>